| Loans - Summary of Amortized Cost Basis of Collateral Dependent Loans By Class of Loans (Parenthetical) (Detail) | Mar. 31, 2020  USD ($) | 
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| Commercial and Industrial | Commercial Term Loan | |
| Loans And Leases Receivable Disclosure [Line Items] | |
| Loans receivable, secured by real estate | $ 525,000 | 
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- Definition Loans receivable cash collateral for dependent loans. No definition available. 
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available. 
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